From 6d27ddf97c68d2e80925dc25b790d598170b7a0f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20Stan=C4=9Bk?= <jstanek@redhat.com>
Date: Thu, 8 Jul 2021 14:08:31 +0200
Subject: [PATCH] Use OpenSSL 1.0 API
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- Pass non-const pointer to BIO_new

  In legacy OpenSSL, the method parameter for BIO_new is not marked const,
  although the function does not need it to be mutable.
  This is likely an oversight in the interface.

  The provided "fix" is potentially dangerous,
  as casting away `const`-ness is potentially an undefined behaviour.
  Since the code around assumes it is constant anyway,
  it *should* be fine here – but use with care.

- Remove const-classifier for SSL_SESSION callback argument

  In legacy OpenSSL, the parameter is expected to be mutable.
  Using `const` prevents passing the method as a function pointer
  to other OpenSSL API functions.

- Provide GetCipherValue wrapper for non-const strings

- Sanitize inputs into PBKDF2

- Setup ECDHE curve negotiation

  - SSL_OP_SINGLE_ECDH_USE is no-op and default in OpenSSL 1.1,
    but should be specified in OpenSSL 1.0
  - SSL_CTX_set_ecdh_auto() is presumably the same case;
    does not even exist in OpenSSL 1.1

  Without this setup, ECDHE curve negotiation is broken: rhbz#1910749

Signed-off-by: Jan Staněk <jstanek@redhat.com>
---
 src/node_crypto.cc        | 30 ++++++++++++++++++++++++++++--
 src/node_crypto.h         |  4 ++++
 src/node_crypto_bio.cc    |  4 ++++
 src/node_crypto_common.cc |  8 ++++++++
 4 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/src/node_crypto.cc b/src/node_crypto.cc
index e472892b68..0cc97f99ea 100644
--- a/src/node_crypto.cc
+++ b/src/node_crypto.cc
@@ -123,7 +123,11 @@ template int SSLWrap<TLSWrap>::SetCACerts(SecureContext* sc);
 template void SSLWrap<TLSWrap>::MemoryInfo(MemoryTracker* tracker) const;
 template SSL_SESSION* SSLWrap<TLSWrap>::GetSessionCallback(
     SSL* s,
+#if OPENSSL_IS_LEGACY
+    unsigned char *key,
+#else
     const unsigned char* key,
+#endif
     int len,
     int* copy);
 template int SSLWrap<TLSWrap>::NewSessionCallback(SSL* s,
@@ -1189,6 +1193,10 @@ void SecureContext::SetECDHCurve(const FunctionCallbackInfo<Value>& args) {
   THROW_AND_RETURN_IF_NOT_STRING(env, args[0], "ECDH curve name");
 
   node::Utf8Value curve(env->isolate(), args[0]);
+#if OPENSSL_IS_LEGACY
+  SSL_CTX_set_options(sc->ctx_.get(), SSL_OP_SINGLE_ECDH_USE);
+  SSL_CTX_set_ecdh_auto(sc->ctx_.get(), 1);
+#endif
 
   if (strcmp(*curve, "auto") == 0)
     return;
@@ -1746,7 +1754,11 @@ void SSLWrap<Base>::ConfigureSecureContext(SecureContext* sc) {
 
 template <class Base>
 SSL_SESSION* SSLWrap<Base>::GetSessionCallback(SSL* s,
+#if OPENSSL_IS_LEGACY
+                                               unsigned char* key,
+#else
                                                const unsigned char* key,
+#endif
                                                int len,
                                                int* copy) {
   Base* w = static_cast<Base*>(SSL_get_app_data(s));
@@ -5921,9 +5933,23 @@ struct PBKDF2Job : public CryptoJob {
   }
 
   inline void DoThreadPoolWork() override {
-    auto salt_data = reinterpret_cast<const unsigned char*>(salt.data());
+    static const char * const empty = "";
+
+    auto pass_data = reinterpret_cast<const char *>(empty);
+    auto pass_size = int(0);
+    auto salt_data = reinterpret_cast<const unsigned char *>(empty);
+    auto salt_size = int(0);
+
+    if (pass.size() > 0) {
+      pass_data = pass.data(), pass_size = pass.size();
+    }
+    if (salt.size() > 0) {
+      salt_data = reinterpret_cast<const unsigned char *>(salt.data());
+      salt_size = salt.size();
+    }
+
     const bool ok =
-        PKCS5_PBKDF2_HMAC(pass.data(), pass.size(), salt_data, salt.size(),
+        PKCS5_PBKDF2_HMAC(pass_data, pass_size, salt_data, salt_size,
                           iteration_count, digest, keybuf_size, keybuf_data);
     success = Just(ok);
     Cleanse();
diff --git a/src/node_crypto.h b/src/node_crypto.h
index 7bce7706a9..780e1893f4 100644
--- a/src/node_crypto.h
+++ b/src/node_crypto.h
@@ -234,7 +234,11 @@ class SSLWrap {
   static void AddMethods(Environment* env, v8::Local<v8::FunctionTemplate> t);
 
   static SSL_SESSION* GetSessionCallback(SSL* s,
+#if OPENSSL_IS_LEGACY
+                                         unsigned char* key,
+#else // OPENSSL_IS_LEGACY
                                          const unsigned char* key,
+#endif // OPENSSL_IS_LEGACY
                                          int len,
                                          int* copy);
   static int NewSessionCallback(SSL* s, SSL_SESSION* sess);
diff --git a/src/node_crypto_bio.cc b/src/node_crypto_bio.cc
index 55f5e8a5a3..c2a44fdb86 100644
--- a/src/node_crypto_bio.cc
+++ b/src/node_crypto_bio.cc
@@ -31,7 +31,11 @@ namespace node {
 namespace crypto {
 
 BIOPointer NodeBIO::New(Environment* env) {
+#if OPENSSL_IS_LEGACY
+  BIOPointer bio(BIO_new(const_cast<BIO_METHOD *>(GetMethod())));
+#else
   BIOPointer bio(BIO_new(GetMethod()));
+#endif
   if (bio && env != nullptr)
     NodeBIO::FromBIO(bio.get())->env_ = env;
   return bio;
diff --git a/src/node_crypto_common.cc b/src/node_crypto_common.cc
index 6c3bb0b1b6..d1d9edd6cd 100644
--- a/src/node_crypto_common.cc
+++ b/src/node_crypto_common.cc
@@ -392,6 +392,14 @@ MaybeLocal<Value> GetCipherValue(Environment* env,
 
   return OneByteString(env->isolate(), getstr(cipher));
 }
+MaybeLocal<Value> GetCipherValue(Environment* env,
+    const SSL_CIPHER* cipher,
+    char* (*getstr)(const SSL_CIPHER* cipher)) {
+  if (cipher == nullptr) {
+    return Undefined(env->isolate());
+  }
+  return OneByteString(env->isolate(), const_cast<const char *>(getstr(cipher)));
+}
 
 MaybeLocal<Value> GetCipherName(Environment* env, const SSL_CIPHER* cipher) {
   return GetCipherValue(env, cipher, SSL_CIPHER_get_name);
-- 
2.31.1